LEGUP [BUG] [Light-Up] Bug with Satify Number Case rule

Description

Something really weird is happening in a student 'solution' to a lightup puzzle below (see screenshot). Note that the chosen rule is the 'Satisfy Number' case rule, but a bulb is placed on the board that has nothing to do with any number cell .. and yet the rule checks out!

One could possibly take the fact that there is only one 'branch' created by this case rule as weird itself ... but note that a case rule sometimes generates just one case, so in and of itself that is not necessarily incorrect. But in this case, I have no idea how many cases there should be ... since it just doesn't make sense to put down a lightbulb in this square given that particular case rule!!

Indeed, I wonder how the student even got to get to this point ... I can see two ways the student could have gotten this:

Use the '+' icon to create a new transition, place a lightbulb on the board, and then select the case rule
Place the lightbulb and select any Direct rule, then go back to the transition and change the rule to the case rule

I tried going back an earlier point in this proof, and place the lightbulb with that case rule .... but then it (correctly!) doesn't check out ... so why does it check out at this point of the proof? Very strange ... I am reminded of another very strange lightup bug, also involving the Satisfy Number case rule, and where the checking or not checking out of the rule also seems to be sensitive to changes to the board state that seem to have nothing to do with it .. it's issue #555